Wrench



March 6, 1945.v A. BoYNToN 2,370,837

WRENCH Original Filed April 8, 1959 A TTOR/VE Y i Patented Mar.4 o, 1945 233703837' f W-RENGH Aiexanarnbyntamfsan Antonio; Tem-sida si Martin executrix of said- Alexander Boynton,

1- aeceaseu original.

appliance April 8'.. 1939; serial. Nw

' 2 'ii6Q75'9Lv Divided. and this` application October es; 1942, serrer-Nb: l463,400A y 1 clarin;y (ci. six- 179).v

This application is; a. dii'lision.y ofi. mypending applicationSerial No. .2'6fi,r',59}` led`April 8; 1939-; andiissued asBatentl No. 2,330,201'v of Sept.28; 1943.

My invention topipe vv-rencl'ies..` y

The4 objects aretoproyidea Wrench that (1l), will'lnot mash the.pipe,;.(2 will'.not'deeply` score the. pipe.,l (3). willcl'o'se evenly `uponga substantial;

1y complete. circumferentialisurface croie. pipe..

(4l -Will gripfthe pipe with. uniformly increasing. force as increasing f'orce"i's` applied to, Qperate.it, and (5), Will-automatically return tlepipegripping dogs to their starting'position .each time. the wrench is removed fromthepipe.` l

I attainthe' foregoing objects by means of `two: shells or.j'aws;,each shellorijw. bei-nghinged or' pivo-ted on the other.'shelllonjaw,h 'oneshellor relates,to.. Wrenches, particularly jaw. being connect-edito the wrench. handle andl the other shell' or. jaw! being 'operatedlupo-n an arm androller. or cam. member vconnected to? the handle so as to` permit urgingjtlie.jaws.together 'upon the pipe; as Wil1"more' clearly' ap# pear from the accompanying-drawing; in which: Fig; l'is a top View of the invention;v Fig; 2 is" a topV oriplan View;`

Fig. 3 is a View lin-'elevationcftne'jassembiii of'Fig. 1

Fig. distan in Fig: 5;

partly.'` in section;

endvietv oftheplate portion'sho'wn p 214" is compressing bythe: stop4k members" Fig. 7 is a plan view of the upper holder plate shown in Fig. 2 and Fig. 8 is a sectional view taken on the section line 8--8 of Fig. 7.

Similar reference characters refer to similar parts throughout the several views.

In thev embodiment ofthe invention illustrated in the drawing, the handle member Idh and the jaw member Id connected thereto are hinged or pivoted to the jaw member I5 by means of the hinge bolt or pivot I6. .An arm member or yoke I1 is hinged or pivoted to the handle member Idh by means of a hinge bolt vor pivot I9 which passes through a boss Ida of the handle member. An eccentric lever 0r bell crank lever I8 is pivoted in such a manner as to engage the other clamp jaw I5 on movement of the handle member Idh and the eccentric lever or bell crank lever I8 in a pipe engaging direction, being preferably hinged orpivoted 4 ait one end Vof thel yoke or arm-member IIby meansof ahinge bolt 20 The ar'mportion I'B'aVV of lthe` bellcrank'lvr I8 ispreferably. in the form. .offan eccentric yorcani adaptedto operate upony the forward surface portion, liseofA the? arm member-ld connected to-the shell or jayvvmemben I.5 in'v sucl'iamanner asy to; urge thel. eccentricpipe-gripperkdogs .ZI `,`.li'a'ving cam. suriacsthereon, toward 'the l pipe'. I`3 asrtlie lever ann I-lim'ov'ed.L inadirection4 sempcircular trough zld to"y the" ccrrespcnc' g gripper dogs* 2 I by' means oi" Welds'" 2"I c; f'or' feiampie; j H.. n' Each of* the lipp'ortimi's* 25'a (Fig' 5) hasir'e' sliding clearance within the circular troughs or grooves Idc of the jaws and 2Id (Fig. 4) of the dogs. Since one of the dog stops Idd is fastened to the corresponding jawmember I4, to which the handle Idh is connected, by means of the weld portion Ide, andthe other dog stop 1Idd is fastened within and upon the otherjaw member. I5 by means of another weld portion Ide, and `since the spring stop members 2lb are fastened to the gripper dogs 2| by means of weld portions y2Ic, it is apparent that the eccentric ory cam gripper dogs 2| will b e stopped in the f positions shown in Fig. 2 by the landing of stops 2lb upon the dog stops I ddtby theexpansive force of the coiled springs 2d, which are confined or stopped at the other ends by means o f the plates 2-5 or plate portions 25a. The spring members 2d are installed under suicient compression to accomplish such landing of the spring stops 2lb upon the dog stops I4d and to permit the full travel of the pipe gripper dogs 2i without having the springs fully compressed.

The cam-surfaced or eccentric pipe gripper dogs 2i, with their partially contained springs 24, are held assembled within the jaw members I4 and I by means of flanged holder plates 22 (Figs. 1 and 2) which are held in place by means of screws 23 (Fig. 1) which pass through openings 22h (Figs. 7 and 8) in each of the plate members. The inner flange 22a of each of the plates 22 (Fig. 1) is received into or within one of the grooves 2Ie` of the gripper dogs 2| (Fig. e) in which the iianges are slidable. The other or outer flange 22a iits closely over the outside of the jaw members I4 and I5, each of the plates 22 being attached to the corresponding jaw members by means of the screws 23 which pass into and are secured in threaded openings in the jaw members.

In order to apply the wrench as illustrated in the drawing to a pipe which is engaged, the bell crank lever I8 is first turned in a clockwise direction until it is approximately in a position so that the longer arm is substantially at right angles to the handle member I4h. The cam or eccentric IBa will then release the arm I5a connected to the jaw member I5. The bell crank lever, I8 and the arm member I'I are then moved outwardly in a counter-clockwise direction until the arm I5a is free of the cam I8a and the yoke or arm member I'I. The jaw members may then be opened by swinging the jaw member I5 in a clockwise direction, for example, and the pipe I3 may then be inserted in place against the inner curved surface of the jaw member I 4. For operating convenience, the bumper extension I5b is provided in such a position on the jaw member I5 that in the opening of the jaws it will engage the surface I4b jaw members forwardly with respect to the spring members 24, causing a. compression of the springs, the throw or movement of the pipe gripper dogs 2l being suillcient to completely embed the teeth 2Ia. upon the pipe I3 before the flanges 22a have reached the limit of their travel in grooves 2Ie and before the springs 24 have been completely compressed by the lip members 25a. In other words, by the clockwise movement of the wrench jaws around the gripper dogs 2i, the inner contacting surfaces 28 (Fig. 4) of the jaw members I4 and I5 move on the cam surfaces 30 on the upper surfaces of the gripper dcgs to a higher position on the said cam surfaces 30, thereby forcing the gripper dogs 2i inwardly during the said clockwise movement of the wrench.

When the wrench is released from the pipe, the springs 24 will return the dogs 2i to their initial lposition as shown in Fig. 2 of the drawing. It will be understood, of course, that the terms clockwise and counter-clockwise" are used by on the corresponding end of the jaw member I4 'after the wrench has been opened wide enough to admit the pipe I3.' The pipe may then be gripped by returning the arm I5a, the yoke member I1, and the lever I 8, by which movement the eccentric or cam I8a will engage the arm I5a in the position shown in Fig` 1 of the drawing.

A pipe wrench comprising: two jaw members pivoted together at one end and provided with means to hold the members in pipe engaging position, each of said jaw members having eccentrically disposed semicircular grooves; eccentric pipe gripper dogs each having a semicircular groove to cooperate with an adjacent one of said semicircular grooves of said jaw members; a plate secured to each jaw member and having a lip to enter the semicircular groove of the adjacent dog; a spring stop secured to each dog at the end thereof remote from said plate, said dogs having eccentrically disposed curved grooves in their sides; coil springs in said grooves and engaging respectively said plates and said spring stops; holder plates secured to said jaw members and having flanges to ride in said side grooves and thereby retain said dogs against lateral displacement and avoid lateral pressure on said springs.

ALEXANDER BOYNTON. 

